This has important implications for the recurrence of this cancer following chemotherapy with gemcitabine, where an increase is shown in the expression of CXCR2 ligands, including CXCL1, in pancreatic ductal adenocarcinoma [192] and in the metastatic site of this tumor [185]. This evidence concerns the gene CXCR2 and pancreatic ductal adenocarcinoma.